As far as boundaries, you really need to let her that you are not the only parent for the children and that you will not allow that, take charge but don't be angry nor mean, be heard but not controlling, you are standing up for yourself and your kids now.
You should document everything and take pictures etc, whatever proof you can use in case it goes down the legal path down the road.
I have plenty of pic, videos, documents just in case she tries to take my kids away, you should too.
